The red in redheads' hair is thought to put them at increased risk of the dangerous skin cancer melanoma, even if they don't spend a lot of time in the sun, according to a new study. Study co-author Dr. David Fisher and his research team first uncovered the apparent link between red hair pigment and melanoma last fall. That study used genetically altered mice that had been given a mutant gene that increased their risk of contracting the skin cancer.